Resumen:
Se estudiaron cuatro genes candidatos para tamaño de la camada. Los genes receptores de los estrógenos, receptor de la prolactina, retinol-binding protein 4 y alpha 1,2 fucosyltransferasa fueron evaluados para medir sus asociaciones con el número de lechones nacidos totales (LNT), lechones nacidos vivos (LNV), peso de la camada al nacimiento (PNAC) y al destete (PAJ21), lechones destetados (LD), y el valor de criá de la progenie de la cerda (VRDC). Se estudiaron 300 hembras porcinas York-Landrace de dos niveles de producción (NP): nivel alto (NA) y nivel bajo (NB) y estos niveles, a su vez, se dividieron en 3 grupos cada uno de acuerdo a la paridad de las marranas. Se utilizaron pruebas de Chi cuadrada para analizar las frecuencias génicas y genotípicas estableciendo el equilibrio de Hardy-Weinberg, se hicieron análisis de varianza donde la comparación de medias se hizo con contrastes ortogonales y se calcularon distancias genéticas para construir árboles filogenéticos. Las hembras con alta productividad se asociaron con una mayor frecuencia del alelo B del gen ESR (p<0.05) Y no se detectaron animales homocigotos BB.
Descripción:
Four candidate genes were studied for litter size. Estrogen receptor genes, prolactin receptor, retinol-binding protein 4 and alpha 1,2 fucosyltransferase were evaluated to measure their associations with the number of total born piglets (LNT), live born piglets (LNV), weight of the litter at birth (PNAC) and at weaning (PAJ21), weaned piglets (LD), and the breeding value of sow progeny (VRDC). We studied 300 York-Landrace pigs with two production levels (NP): high (NA) and low (NB) levels, and these levels, in turn, were divided into 3 groups each according to the parity of the sows Chi square tests were used to analyze gene and genotypic frequencies establishing the Hardy-Weinberg equilibrium, analysis of variance was made where the comparison of means was made with orthogonal contrasts and genetic distances were calculated to build phylogenetic trees. The females with high productivity were associated with a higher frequency of the B allele of the ESR gene (p<0.05) and no BB homozygous animals were detected.